Standards with the same topic and subject but for other grades
Estimate the sum, difference, product, and quotient of whole number computations.
sums, differences, and products do not exceed five digits;
estimate sums, differences, products, and quotients of whole numbers;
Estimate the sum of two whole numbers whose sum is 99 or less and recognize whether the estimation is reasonable (e.g., 27 + 41 is about 70, because 27 is about 30 and 41 is about 40, and 30 + 40 is 70). (a)
divisors do not exceed two digits; or
Estimate whole number sums, differences, products, and quotients.
Select appropriate methods and tools from among paper and pencil, estimation, mental computation, and calculators according to the context and nature of the computation in order to compute with whole numbers.
To estimate means to determine a number that is close to the exact amount. When asking for an estimate, teachers might ask, “About how much?” or “About how many?” or “Is this about 10 or about 50?”
Demonstrate fluency with addition and subtraction within 10. (b)
Combine parts contained in larger numbers up to 20 by using related combinations (e.g., 9 + 7 can be thought of as 9 broken up into 2 and 7; using doubles, 7 + 7 = 14; 14 + 2 = 16 or 7 broken up into 1 and 6; making a ten, 1 + 9 = 10; 10 + 6 = 16).